EFFECT OF INITIAL CONTACT LOCATION ON MULTIASPERITY NANOCONTACT: QUASICONTINUUM SIMULATION

WU-GUI JIANG,ZHENG-WEI WANG,SHUANG XU 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2014 NANO Vol.9 No.1

Two nanocontact models with di®erent initial contact locations are built to simulate the processof the multiasperity nanocontact for investigating the e®ect of initial contact location on thenanocontact process by using the quasicontinuum method. The indenter is initially located on thetop of the middle wave crest (MWC) of the substrate and the top of the wave trough on the leftside (LWT) of the substrate, respectively. The microscopic deformation mechanism, the load –displacement curve and the nanohardness – displacement curve are examined. It is found that thedeformation mechanisms in the two multiasperity contact models are di®erent. During the initialcontact stage, in the MWC model, the twinning deformation dominates the whole contact pro-cess, while in the LMT model many Lomer-Cottrell locks are generated in the copper substrate,which inhibits the occurrence of twinning deformation.

Effects of 3D contraction on pebble flow uniformity and stagnation in pebble beds

Wu, Mengqi,Gui, Nan,Yang, Xingtuan,Tu, Jiyuan,Jiang, Shengyao Korean Nuclear Society 2021 Nuclear Engineering and Technology Vol.53 No.5

Pebble flow characteristics can be significantly affected by the configuration of pebble bed, especially for HTGR pebble beds. How to achieve a desired uniform flow pattern without stagnation is the top priority for reactor design. Pebbles flows inside some specially designed pebble bed with arc-shaped contraction configurations at the bottom, including both concave-inward and convex-outward shapes are explored based on discrete element method. Flow characteristics including pebble retention, residence-time frequency density, flow uniformity as well as axial velocity are investigated. The results show that the traditionally designed pebble bed with cone-shape bottom is not the most preferred structure with respect to flow pattern for reactor design. By improving the contraction configuration, the flow performance can be significantly enhanced. The flow in the convex-shape configuration featured by uniformity, consistency and less stagnation, is much more desirable for pebble bed design. In contrast, when the shape is from convex-forward to concave-inward, the flow shows more nonuniformity and stagnation in the corner although the average cross-section axial velocity is the largest due to the dominant middle pebbles.

Prediction of the remaining time and time interval of pebbles in pebble bed HTGRs aided by CNN via DEM datasets

Wu Mengqi,Liu Xu,Gui Nan,Yang Xingtuan,Tu Jiyuan,Jiang Shengyao,Qian Zhao 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.1

Prediction of the time-related traits of pebble flow inside pebble-bed HTGRs is of great significance for reactor operation and design. In this work, an image-driven approach with the aid of a convolutional neural network (CNN) is proposed to predict the remaining time of initially loaded pebbles and the time interval of paired flow images of the pebble bed. Two types of strategies are put forward: one is adding FC layers to the classic classification CNN models and using regression training, and the other is CNNbased deep expectation (DEX) by regarding the time prediction as a deep classification task followed by softmax expected value refinements. The current dataset is obtained from the discrete element method (DEM) simulations. Results show that the CNN-aided models generally make satisfactory predictions on the remaining time with the determination coefficient larger than 0.99. Among these models, the VGG19þDEX performs the best and its CumScore (proportion of test set with prediction error within 0.5s) can reach 0.939. Besides, the remaining time of additional test sets and new cases can also be well predicted, indicating good generalization ability of the model. In the task of predicting the time interval of image pairs, the VGG19þDEX model has also generated satisfactory results. Particularly, the trained model, with promising generalization ability, has demonstrated great potential in accurately and instantaneously predicting the traits of interest, without the need for additional computational intensive DEM simulations. Nevertheless, the issues of data diversity and model optimization need to be improved to achieve the full potential of the CNN-aided prediction tool

Meta-analysis of the Efficacy of Sorafenib for Hepatocellular Carcinoma

Wang, Zhao,Wu, Xiao-Ling,Zeng, Wei-Zheng,Xu, Gui-Sen,Xu, Hui,Weng, Min,Hou, Juan-Ni,Jiang, Ming-De Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.2

Purpose: By carrying out a meta-analysis of randomized controlled trials that compared sorafenib or combined chemotherapy with placebo or combined chemotherapy, the effectiveness of sorafenib in hepatocellular carcinoma was evaluated in the present study, which also provided clinical practice guidelines of evidence-based-medicine. Methods: We reviewed PubMed citations concerning sorafenib treating hepatocellular carcinoma in randomized controlled trials from Jan 2000 to July 2012. All the literature was extracted by Cochrane systematic reviews and underwent meta-analysis with RewMan 5.0 software. Results: Finally, four papers documenting randomized controlled studies were included. Compared with controls, sorafenib was shown to significantly increase overall survival (OS), time to progression (TTP), and disease control rates (DCR), but not the time to symptom progression (TTSP) in hepatocellular carcinoma patients. The incidence of grade-III/IV adverse reactions, including hand-foot-skin reactions, diarrhea, hypertension and skin rash or desquamation, in sorafenib treatment group was higher than that in controls. However, there was no significant difference in the incidence of hypodynamia between the two groups. Conclusions: Sorafenib exerts significant curative effects in hepatocellular carcinoma.

Iron-doped chitosan microsphere for As(III) adsorption in aqueous solution: Kinetic, isotherm and thermodynamic studies

Xiaoyu Lin,Leli Wang,Shi Jiang,Longzhe Cui,Gui-Ping Wu 한국화학공학회 2019 Korean Journal of Chemical Engineering Vol.36 No.7

Iron-doped chitosan microsphere was prepared successfully and employed for effective adsorption of As(III). The results showed that the adsorption capacity benefited from the increase of iron content, and the maximum adsorption capacity was achieved at pH=8. According to the study of adsorption kinetics, adsorption rate was controlled by liquid film diffusion at a lower rotational speed, while it was controlled by chemical reaction rate at a higher rotational speed. The Freundlich and Temkin models exhibited a better fit to adsorption isotherm data, which indicated the adsorption of As(III) on iron-doped chitosan microsphere was chemisorption and the active sites of adsorbents were non-uniform distributed. Adsorption process was a spontaneous exothermic reaction because its ΔG and ΔH were negative. In presence of cations (Cd2+, Pb2+ or Zn2+) in solution, the iron-doped chitosan microsphere also showed the significant removal of As(III). However, the existence of anions (NO3 , SO4 2 or PO4 3) inhibited the As(III) removal at different level. PO4 3 showed the most significant side effects on the removal of As(III) by iron-doped chitosan microsphere. The used iron-doped chitosan adsorbent can be effectively regenerated using 1.0mol·L1 NaOH solution, and the adsorption efficiency decreased only 15.69% after being reused three times. The results of XPS, FT-IR showed that the adsorption was mainly achieved by the coordination interaction between As (III) and doped Fe in adsorbent.

Radixin Knockdown by RNA Interference Suppresses Human Glioblastoma Cell Growth in Vitro and in Vivo

Qin, Jun-Jie,Wang, Jun-Mei,Du, Jiang,Zeng, Chun,Han, Wu,Li, Zhi-Dong,Xie, Jian,Li, Gui-Lin Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.22

Radixin, a member of the ERM (ezrin-radixin-moesin) family, plays important roles in cell motility, invasion and tumor progression. It is expressed in a variety of normal and neoplastic cells, including many types of epithelial and lymphoid examples. However, its function in glioblastomas remains elusive. Thus, in this study, radixin gene expression was first examined in the glioblastoma cells, then suppressed with a lentivirus-mediated short-hairpin RNA (shRNA) method.We found that there were high levels of radixin expression in glioblastoma U251cells. Radixin shRNA caused down-regulation of radixin gene expression and when radixin-silenced cells were implanted into nude mice, tumor growth was significantly inhibited as compared to blank control cells or nonsense shRNA cells. In addition, microvessel density in the tumors was significantly reduced. Thrombospondin-1 (TSP-1) and E-cadherin were up-regulated in radixin- suppressed glioblastoma U251 cells. In contrast, MMP9 was down-regulated. Taken together, our findings suggest that radixin is involved in GBM cell migration and invasion, and implicate TSP-1, E-cadherin and MMP9 as metastasis-inducing factors.

Influence of Psychological Factors in Primary Dysmenorrhea Patients on De qi : a Secondary Analysis of a Randomized Controlled Trial

Hu Ni-juan,Li Chun-hua,Wang Pei,Wu Gui-wen,Ma Liang-xiao,Zhu Jiang 사단법인약침학회 2023 Journal of Acupuncture & Meridian Studies Vol.16 No.1

Background: De qi , the needling sensation, is important in acupuncture treatment. Almost all studies believe that deep needling and manipulation could achieve a significant de qi sensation. However, relatively few studies have examined the effect of psychological factors on de qi, and those that did often reached different conclusions. Objectives: To explore the influence of psychologic factors on de qi in patients with primary dysmenorrhea (PD). Methods: Sixty-eight PD patients with cold and dampness stagnation were randomly allocated to de qi (deep insertion using thick needles, with manipulation, n=17) and non-de qi groups (shallow insertion using thin needles, without manipulation, n=51). Both groups received bilateral needling at Sanyinjiao (SP6) for 30 min. De qi was assessed using the Acupuncture De qi Clinical Assessment Scale (ADCAS). The patients’ acupuncturerelated anxiety and their expectations of the relationship between needle sensation and curative effect were evaluated using a five-point and four-point scale, respectively. Results: Within the de qi group, all patients experienced the de qi sensation, although anxiety levels were unrelated to de qi. Patients’ expectations correlated negatively with de qi timing, and positively with electric sensation. Within the non-de qi group, 59.5% of patients experienced de qi. Between those who experienced it and those who did not, no significant differences were found in anxiety levels, although patients’ expectations differed significantly. Among patients who experienced de qi sensations in the non-de qi group, anxiety and throbbing were positively correlated. Additionally, patients’ expectations correlated positively with de qi intensity, as well as coldness, and numbness. Conclusion: Psychological factors should be considered when studying de qi since PD patients’ expectations could influence the de qi sensation at SP6.

RALY RNA Binding Protein-like Reduced Expression is Associated with Poor Prognosis in Clear Cell Renal Cell Carcinoma

Cui, Zhi-Wen,Xia, Ye,Ye, Yi-Wang,Jiang, Zhi-Mao,Wang, Ya-Dong,Wu, Jian-Ting,Sun, Liang,Zhao, Jun,Fa, Ping-Ping,Sun, Xiao-Juan,Gui, Yao-Ting,Cai, Zhi-Ming Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.7

The molecular mechanisms involved in the progression of clear cell renal cell carcinomas (ccRCCs) are still unclear. The aim of this study was to analyse the relationships between expression of RALYL and clinical characteristics. In 41 paired samples of ccRCCs and adjacent normal tissues, we used real-time qPCR to evaluate the expression of RALYL mRNA. RALYL protein levels were determined in 146 samples of ccRCC and 37 adjacent normal tissues by immunohistochemistry. Statistical analysis was used to explore the relationships between expression of RALYL and the clinical characteristics (gender, age, tumor size, T stage, N stage, M stage, survival times and survival outcome) in ccRCC. In addition, these patients were follow-up period 64 months (range: 4~116months) to investigate the influence on prognosis. We found significantly differences between ccRCC tissues and normal tissues (p<0.001, paired-sample t test) in mRNA levels of RALYL. Immunohistochemistry analyses in 146 ccRCC samples and 37 adjacent normal tissues showed significantly lower RALYL protein levels in ccRCC samples (${\chi}^2$-test, p<0.001), inversely correlating with tumour size (p=0.024), T stage (0.005), N stage (p<0.001) as well as M stage (p=0.019), but not age (p=0.357) and gender (p=0.348). Kaplan-Meier survival analysis demonstrated that people with lower level of RALYL expression had a poorer survival rate than those with a higher level of RALYL expression, significantly different by the log-rank test (p=0.011). Cox regression analysis indicated that RALYL expression (p=0.039), N stage (p=0.008) and distant metastasis (p<0.001) were independent prognosis factors for the overall survival of ccRCC patients. We demonstrated that the expression of RALYL was significantly low in ccRCC and correlated with a poor prognosis in a large number of clinical samples. Our findings showed that RALYL may be a potential therapeutic target as well as a poor prognostic factor.

Prognostic Factors Influencing Clinical Outcomes of Malignant Glioblastoma Multiforme: Clinical, Immunophenotypic, and Fluorescence in Situ Hybridization Findings for 1p19q in 816 Chinese Cases

Qin, Jun-Jie,Liu, Zhao-Xia,Wang, Jun-Mei,Du, Jiang,Xu, Li,Zeng, Chun,Han, Wu,Li, Zhi-Dong,Xie, Jian,Li, Gui-Lin Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.3

Malignant glioblastoma multiforme (GBM) is the most malignant brain tumor and despite recent advances in diagnostics and treatment prognosis remains poor. In this retrospective study, we assessed the clinical and radiological parameters, as well as fluorescence in situ hybridization (FISH) of 1p19q deletion, in a series of cases. A total of 816 patients with GBM who received surgery and radiation between January 2010 and May 2014 were included in this study. Kaplan-Meier survival analysis and Cox regression analysis were used to find the factors independently influencing patient progression free survival (PFS) and overall survival (OS). Age at diagnosis, preoperative Karnofsky Performance Scale (KPS) score, KPS score change at 2 weeks after operation, neurological deficit symptoms, tumor resection extent, maximal tumor diameter, involvement of eloquent cortex or deep structure, involvement of brain lobe, Ki-67 and MMP9 expression level and adjuvant chemotherapy were statistically significant factors (p<0.05) for both PFS and OS in the univariate analysis. Cox proportional hazards modeling revealed that age ${\leq}50$ years, preoperative KPS score ${\geq}80$, KPS score change after operation ${\geq}0$, involvement of single frontal lobe, deep structure involvement, low Ki-67 and MMP9 expression and adjuvant chemotherapy were independent favorable factors (p<0.05) for patient clinical outcomes.

Triterpenoid saponins from Clinopodium chinense (Benth.) O. Kuntze and their biological activity

Yin-Di Zhu,Jing-Yi Hong,Feng-Da Bao,Na Xing,Ling-Tian Wang,Zhong-Hao Sun,Yun Luo,Hai Jiang,Xudong Xu,Nai-Liang Zhu,Hai-Feng Wu,Gui-Bo Sun,Jun-Shan Yang 대한약학회 2018 Archives of Pharmacal Research Vol.41 No.12

Four new ursane-type triterpenoid saponins, clinopoursaponins A–D (1–4), six new oleanane-type triterpenoid saponins, clinopodiside VII–XII (5–10), as well as eight known triterpene analogues (11–18), were isolated from the aerial parts of Clinopodium chinense (Benth.) O. Kuntze. The structures of the new compounds were determined based on extensive spectral analyses, including 1D (1H and 13C) and 2D NMR experiments (COSY, NOESY, HSQC, 2D TOCSY, HSQC-TOCSY and HMBC), HR-ESI-MS and chemical methods. Compounds 1–18 were evaluated for their protective effects against anoxia/reoxygenation-induced apoptosis in H9c2 cells and cytotoxicities against murine mammary carcinoma cell line 4T1. Compounds 8, 9 and 18 exhibited significant protective effects, while compound 1 exhibited cytotoxic activity with IC50 value of 7.4 μm compared to 7.6 μm for the positive control 10-hydroxycamptothecin.